Timepiece movement with intermittent seconds indicator



1952 FRITZ-ANDRE ROBERT-CHARRUE 2,580,597

' TIMEIPIECE MOVEMENT WITH INTERMITTENT SECONDS INDICATOR Filed Jun 2,1949 AHorn LY Patented Jan. 1, 1952 TIMEPIECE MOVEMENT WITH INTERMIT-TENT SECONDS INDICATOR Fritz-Andre Robert-Charrue, Le Locle,Switzerland, assignor to Ebauches S. A., Neuchatel, Switzerland, a Swissfirm Application June 2, 1949, Serial No. 96,637 In Switzerland June 9,1948 7 Claims. (CI. 5859) 1 This invention relates to a mechanism ofidling seconds for movements in timepieces, that is to -say, a mechanismin which the seconds hand advances only once every second.

One of the features of this invention is to transform the ordinaryseconds movement of timepieces in which the seconds hand advances fivetimes per second, each time by one-fifth of a second, into the statedimproved mechanism.

This mechanism of idling seconds comprises two coaxial wheels, one ofwhich is a driving wheel, the other one being driven, both forming apart of the gear train of the second hand. These two wheels areconnected through a spring: they have the same number of teeth; thediameter of the driven wheel is slightly smaller than that of thedriving wheel. The said mechanism further comprises a braking orstopping device which cooperates with the two coaxial wheels aforesaid,in such a manner that the pa sage of the teeth of the driving wheel oversaid brak ng or stopping device di places the latter sufficiently toallow the intermittent rotation of the driven wheel, which is broughtabout by the action of the spring.

The driven wheel is geared through a pinion to the wheel of seconds ofthe timepiece. The two coaxial wheels and the braking or stopping deviceare so designed, and their relative motions so regulated, that, at eachintermittent displacement of the driven wheel, the seconds wheel andhand move by one second.

The foregoing and other features of this invention will appear from thefollowing detailed descript on and from the attached drawing, whichrefer, by way of illustration but not of limitation, to an embodimentthereof.

Fig. 1 is a plan view of a watch, the movement of which includes themechanism of idling seconds object of this invention.

Fig. 2 is a plan view of said mechanism.

Fig. 3 is a detailed sectional elevation alon line IIIIII of Fig. 2.

Fig. 4 is a large scale detailed view of the coaxial wheels and brakingor stopping device.

Referring to the drawing, the illustrated watch is designated I. Itsmovement comprises a wheel of seconds 2, driven by pinion 3. A seeondshand I5 is rigidly mounted on the shaft I5 of wheel 2. It furthercomprises two coaxial wheels, 4 and 5, mounted above each other. Thelower wheel 4 (Fig. 2) is a driving Wheel, while the upper wheel 5 isdriven; driven wheel 5 is mounted idle around the end of axis 6 on whichwheel 4 is rigidly mounted. Axis 6 is driven by the watch These twocoaxial wheels are connected by means of a spiral spring "I, the innerend oi which is attached to axis 6, and the outer end of which isattached to a pin borne by driven wheel 5. The diameter of dr ving wheel4 is slightly greater than that of driven wheel 5; however, these twowheels have the same number of teeth, equal to the number of teeth ofthe wheel of seconds 2.

As seen clearly in Fig. 3, driven wheel 5 meshes with p nion 3: thelatter, in turn, meshes with wheel 2 as shown in Fig. 4.

A pawl 9, borne by a spring I0, cooperates with wheels 4 and 5. andtends to oppose their rotation in the direction of arrow I I. A spoke ofwheel 4 carries a pin I2 serving as stop for a spoke of wheel 5. Some ofthe spokes of said wheel 5 are provided with notches I3, which mavreceive pin l2, depending upon the relative setting of wheels 4 and 5:each of these notches I3 has a depth different from that of the othernotches: so that, depending upon which spoke of wheel 5 is set tocooperate w th pin I2, the relative position of the two wheels 4 and 5,upon contact of the pin with the notched spoke, can be varied. A jumperI4, mounted on a spring, cooperates with wheel 2 to eliminate anymotion, oscillation or vibration of the seconds hand I5 after each ofits d splacements.

This mechanism operates as follows:

Wheel 4 being driven in the direction of arrow I I (Fig. 2), pawl 9 issprung and displaced by the teeth of wheel 4. Driven wheel 5 being stoppd, spiral spring I t ghtens. At a given instant, the amp itude of thisdi placement is great eno gh to allow the pas a e of a tooth of wheel 5,the latter being actuated in rotation in the direction of arrow I I byspiral spring I; at that instant, wheel 5 rotates until such of itsspokes as has been set to cooperate with pin I2 comes to strike and restagainst said pin. This rotation of wheel 5 causes, through the meshingtrain of pinion 3 and wheel 2, a displacement of the seconds hand I5corresponding on the time scale I! (diagrammatically represented inFig. 1) of the face of the watch, to one second. To secure this result,the shape of the teeth of wheels 4 and 5 and that of pawl 9 must be soaccurately designed and shaped that, as wheel 4 moves step by step eachone-fifth of a second, pawl 9 should release one tooth of wheel 5 at theend of each fifth movement of wheel 4.

I claim:

1, In a timepiece movement, a mechanism of idling seconds, comprising,as part of the gear train of the seconds hand, a first driving wheel; asecond driven wheel coaxial with said first driving wheel, and havingthe same number of teeth as, and a slightly smaller diameter than, saidfirst driving Wheel, said driven wheel being mounted idle over the shaftof saiddriving. wheel; a springconnecting said first driving and sec.-ond driven wheels; astopping and braking device cooperating with theteeth of said first driv.-.

ing and second driven wheels to allow by its displacement upon thepassage of eachtooth 0f the driving wheel a partial and intermittentrota tion of said driven wheel as a result'ofthe ac tion of said springon said driven wheel.

2. A mechanism as claimed in claim 1 in which said displacement and saidpartial andintermia tent rotation of said driven wheel'are controlled bythe relative profiles of the teeth of said first driving and seconddriven wheels and ofsaid braking and stopping device.

3 -.-,In;a mechanism as-claimedinclaixn La secands wheel,carryingaseconds hand; a; pinion meshing with said seconds wheel andsaiddriven wheel; said partial. and intermittent rotation of said drivenwheel corresponding to a displacement of saidseconds hand of one secondon-the timescale of said timepiece.

4. A mechanism as claimed in claim 1 in which said spring connectingsaiddriving and, driven wheels is a spiral spring attached at one end tosaid shaft of saiddriving wheel, and at the other end to said drivenwheel.

5. A mechanism as claimed in claim lin which saiddriving wheelis-providedwith radial spokes, one'of said spokes carrying a pin, and inwhich said' dri-ven wheelis providedwith radialspokes, and in which-aspoke of said driven wheel abuts said pin at the end of each ofitspartial and intermittent rotation.

6; In a timepiece movement, a mechanism of idling seconds, comprising,as part of the gear train of the seconds hand, a first driving wheel; asecond driven wheel coaxial with said first driving wheel, and havingthe same number of teeth as, and a slightly smaller diameter than, saidfirst driving. wheel, said driven wheel being mounted idle over theshaft of said-driving wheel; a spring connecting said first driving andsaid second driven wheels; a seconds Wheel, carrying a seconds hand; apinion meshing with said seconds Wheel and-said driven wheel; a stoppingand braking device engaging the teeth of said driving and driven wheels,the relative profiles of said teeth and of said device causing thetemporary disengagement of said device from the teeth of said drivenwheel after passage of each tooth-o1 said driving wheel over saiddevice, said disengagement allowing a partial and intermittentrotationof said driven wheel caused by the action of said spring and resultingin a displacement of said seconds, hand of onesecond on-the time scaleof said timepiece.

7. A mechanism as claimed in claim 6 comprising further a .jumpercooperating with said seconds wheel.

FRITZ-ANDRE ROBERT-CHARRUE.

REFERENCES CITED The following references are of recordinthe fileof thispatent;

UNITED STATES PATENTS Number Name Date 224,635 Bonzon Feb. 17, 1880458,745 Benjamin Sept. 1, 1891 FOREIGN PATENTS Number Country Date2.1;489 GreatBritain- Oct.- 3, 1902

